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Egghead.io does great training videos on modern JavaScript stuff, mostly Angular. It’s awesome to see them using CodePen – not just within the videos – but also accompanied by Embedded Pens to deliver working code examples.

Screenshot of one of their lessons:

I’m doing the same thing on my SVG course on CSS-Tricks. Not just because it doesn’t hurt to show off what CodePen can do, but because it’s just the right tool for the job.